County · Texas · United States
Williamson County ZIP codes
20 ZIP codes · 15 cities · FIPS 48491
Key facts
- State
- Texas (TX)
- FIPS code
- 48491
- Population
- 643,889
- Median household income
- $108,309
- Median age
- 37.2
- Land area
- 1,115.8 sq mi (2,890 km²)
- Population density
- 577 / sq mi
- Area codes
- 254, 512, 737
Cities and ZIP codes in Williamson County (15)
About this page
County figures are Census county-level values (ACS 5-year); the ZIP list shows the ZIPs whose primary county this is — a ZIP on a border can also serve neighbouring counties.
Sources: U.S. Census Bureau (2020 county relationship file, ACS 5-year) · GeoNames. Methodology.